Management of Varicella Exposure in a Neonatal Intensive Care Unit

Abstract

We describe the management of an exposure to varicella in a neonatal intensive care unit. Thirty-seven hospital staff members with negative histories of varicella were tested by enzyme-linked immunosorbent assay for antibody to varicella zoster; all were seropositive. None were restricted from clinical duties, were given varicella-zoster immune globulin, or developed disease. Although only 1 of 38 cord serum samples from normal term infants was seronegative, 10 of 22 neonatal intensive care unit infants were seronegative. The high rate of seronegativity among these patients was related to chronological age older than 2 months and to multiple transfusions of packed red blood cells. This probably reflects natural catabolism of maternal antibody and loss of antibody in serum removed from these infants for diagnostic tests. Infants lacking antibody were given varicella-zoster immune globulin. Antibody levels following administration of varicella-zoster immune globulin were directly related to the dose administered.

Chickenpox, Measles, and Mumps

“…None of the exposed mothers or infants developed chickenpox. Lack of transmission despite hospital exposure to an adult with varicella in neonatal intensive care nurseries was also reported by Wang and associates [94] (32 infants), Lipton and Brunell [104] (22 infants), Patou and coworkers [105] (15 infants), Mendez and associates [92] (16 infants), and Gold and coworkers [106] (29 infants).…”

“…Isolation of VZV was successful in 23 of 25 cases in which vesicle fluid was cultured within 3 days after the onset of the rash, but was successful in only 1 of 7 specimens collected 4 to 8 days after onset [109]. In contrast, the virus apparently persists longer in vesicles of zoster patients, in whom 7 of 10 specimens collected later than 3 days after onset were positive [104]. PCR is more sensitive than virus culture.…”

The Influence of Gestational Age on the Loss of Maternal Measles Antibodies in Newborn Infants in North-Eastern Nigeria: A Call for a Review of Measles Immunization Schedule

“…Thus, it is possible that an immature immune system would cause diminished antibody response to measles vaccine in preterm infants. However, a study conducted on the response of preterm infants to Varicella vaccine have demonstrated that by four months of age, the response of preterms was comparable to term and postterm infants (15). This comparable immune response can be explained by the fact that by virtue of their early exposure to extrauterine life, the immune system of a preterm neonate matures rapidly and may be capable of mounting immunological response required for satisfactory uptake of vaccine (8).…”

Varicella zoster virus antibody titers after intravenous zoster immune globulin in neonates, and the safety of this preparation

“…They suggested that this might be due to multiple blood testing with inadvertent plasma VZVIG loss in critical patients, since all four anemic infants needing seven or more transfusions before VZV testing were seronegative [11].…”